The investigations proposed herein are designed to further elucidate basic aspects of the immunobiology of monocytes and tumor-associated macrophages (TAM) from human ovarian tumors. Blood monocytes and peritoneal exudate macrophages from subjects undergoing surgery for benign gynecological conditions wilI serve as controls. In an effort to obtain evidence relevant to understanding the mechanisms regulating the levels of TAM, studies on factor(s) chemotactic for mononuclear phagocytes found in supernatants from primary ovarian carcinoma cultures will be continued and extended. In pursuance of investigations on the cytotoxicity of TAM, the interaction of mononuclear phagocytes with fresh ovarian carcinoma cells will be studied in a colony assay, thus permitting the evaluation of both inhibitory and stimulatory effects on tumor cells. The suppressive activity of TAM on mitogen-induced blastogenesis and on NK activity will be characterized. In an effort to obtain a more comprehensive characterization of the functional properties of TAM, we will study the production of reactive oxygen intermediates, prostaglandins, and procoagulant activity in mononuclear phagocytes from ovarian carcinoma. It is expected that the present study will provide experimental evidence relevant to a better understanding of the role of mononuclear phagocytes in the biology of human neoplasia. (MB)